WICHITA, Kan. (AP) -- A federal judge has granted conditional class action status to the lawsuit against National Beef by workers at its Liberal slaughterhouse.

The decision Thursday by U.S. District Judge Kathryn Vratil certifies the class for purposes of sending notices to workers who might wish to join the lawsuit filed last May.

Workers at the southwest Kansas plant are seeking unpaid wages and overtime on behalf of some 2,000 employees. At issue is the practice of paying meat-processing workers based on so-called gang time, which counts only the time the production line runs.

Vratil has now certified a class comprised of all hourly production workers who have been subject to such compensation in the past three years. She approved Valente Sandoval Barbosa and Carolina Gaytan as class representatives for hourly meat processing workers.